Cylindrical battery anode sealing structure
By employing an annular groove design and an L-shaped rubber sealing ring in the positive electrode sealing structure of the cylindrical lithium-ion battery, the leakage problem caused by shell deformation is solved, and efficient sealing of the positive electrode of the battery is achieved.
Patent Information
- Application Number
- CN202423088822.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-13
- Publication Date
- 2025-11-14
- Estimated Expiration
- 2034-12-13
AI Technical Summary
Traditional cylindrical lithium-ion batteries pose a risk of leakage between the positive electrode post and the positive electrode through hole when the casing deforms.
A cylindrical battery positive electrode sealing structure was designed, which uses a positive electrode post with an annular groove, combined with inner and outer insulating sheets and an L-shaped rubber sealing ring to ensure that the sealing ring can fit tightly against the top surface of the inner cavity of the shell and the outer circumference of the electrode post when the shell is deformed, thus forming a tight seal.
It improves the sealing performance of the positive terminal of the battery, avoids the risk of leakage caused by casing deformation, and ensures that the sealing effect is not affected when the internal pressure of the battery changes.
Smart Images
Figure CN223552568U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to battery packaging technology, and in particular to a positive electrode sealing structure for a cylindrical battery. Background Technology
[0002] Traditional cylindrical lithium-ion batteries consist of a steel cylindrical casing and a cylindrical battery cell housed within the casing's cavity. Cylindrical batteries primarily utilize lithium-ion technology. The casing of a cylindrical lithium-ion battery is closed at the bottom and has a positive electrode through-hole at the top. The positive electrode post of the battery is installed through this through-hole, and an insulating sheet seals the gap between the electrode post and the positive electrode through-hole. When there is significant internal pressure in the cylindrical battery, the casing is prone to deformation, creating a risk of leakage between the positive electrode post and the positive electrode through-hole. Utility Model Content
[0003] The purpose of this invention is to solve the problem of leakage risk in the positive terminal sealing of existing cylindrical batteries, and to provide a cylindrical battery positive terminal sealing structure that is not affected by shell deformation.
[0004] Therefore, this utility model adopts the following technical solution: a cylindrical battery positive electrode sealing structure, wherein the bottom of the cylindrical battery casing is closed and a positive electrode through hole is provided at the top, and the positive electrode post of the cylindrical battery is disposed in the positive electrode through hole. The positive electrode post is characterized by having an annular groove on its outer circumferential surface, and the vertical cross-section of the positive electrode post being "I"-shaped, forming an upper transverse section, a groove section, and a lower transverse section from top to bottom. The groove section of the positive electrode post is located in the positive electrode through hole, and the upper and lower transverse sections are respectively located on the upper side of the top surface of the casing and the top of the inner cavity of the casing. The groove section is covered with an outer insulating sheet, an inner insulating sheet, a metal sheet, and a rubber sealing ring. The outer insulating sheet is positioned... Between the upper transverse section and the top surface of the housing, the inner diameter of the metal sheet is smaller than the outer diameter of the lower transverse section, and the outer diameter is larger than the inner diameter of the inner insulating sheet. The inner diameter of the inner insulating sheet is larger than the inner diameter of the positive electrode through hole. The inner insulating sheet is located between the metal sheet and the top surface of the housing cavity, and the metal sheet is axially limited by the lower transverse section. The rubber sealing ring has an L-shaped vertical cross-section, with a transverse portion and a vertical portion. The outer diameter of the transverse portion is larger than the inner diameter of the positive electrode through hole but not larger than the inner diameter of the inner insulating sheet. The transverse portion has a part sandwiched between the metal sheet and the top surface of the housing cavity, and the vertical portion has a part located between the wall of the positive electrode through hole and the outer peripheral surface of the groove section. When the housing deforms due to excessive internal gas pressure, the top of the housing bulges upward and outward. The internal gas pressure squeezes the metal sheet, and the metal sheet compresses the transverse portion of the rubber sealing ring, ensuring it remains tightly against the top surface of the housing cavity. Under compression, the vertical portion of the rubber sealing ring also deforms and tightly adheres to the outer peripheral surface of the groove section, forming a tight seal and improving the sealing effect.
[0005] As a supplement and improvement to the above technical solution, this utility model also includes the following technical features.
[0006] The outer diameter of the outer insulating sheet is larger than the outer diameter of the upper transverse section, and the inner diameter of the outer insulating sheet is equivalent to the outer diameter of the groove section.
[0007] The inner diameter of the metal sheet is equivalent to the outer diameter of the groove section, and the outer diameter is not greater than the outer diameter of the inner insulating sheet.
[0008] This invention achieves the following beneficial effects: By setting inner and outer insulating sheets, this invention can better achieve insulation between the electrode post and the shell. The built-in sealing ring with an L-shaped structure forms a sealing ring that fits and seals against the top surface of the inner cavity of the shell. When the rubber sealing ring is squeezed by the pressure of the inner cavity of the battery, it can always stick to the top surface of the inner cavity of the shell and undergo compression deformation to stick to the outer circumference of the positive electrode post. This allows the built-in rubber seal to fill the gap between the positive electrode post and the positive electrode through hole of the shell, thereby better ensuring the sealing performance of the battery at the electrode post and preventing it from being affected by shell deformation. Attached Figure Description
[0009] Figure 1 This is a schematic diagram of the structure of this utility model.
[0010] Figure 2 for Figure 1 A magnified view of a portion of point a. Detailed Implementation
[0011] The specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings. The described embodiments are only for illustration and explanation of this utility model and do not constitute the only limitation of this utility model.
[0012] like Figures 1-2 As shown, the cylindrical battery of this utility model includes a steel cylindrical shell 1 and a battery cell housed within the shell cavity. The bottom of the shell 1 is closed, and a positive electrode through hole is provided at the top. A positive electrode post 2 is disposed in the positive electrode through hole of the shell 1, and the positive electrode through hole of the shell 1 and the positive electrode post 2 are sealed by a sealing ring structure. The positive electrode post 2 is formed by riveting a T-shaped component with a cylindrical upper transverse section 21 during assembly, forming an upper transverse section 21, a groove section 22, and a lower transverse section 23 from top to bottom. The outer circumferential surface of the groove section 22 is formed into an annular groove, making the vertical cross-section of the positive electrode post "I" shaped. The groove section 22 of the positive electrode post is located in the positive electrode through hole. The upper transverse section 21 and the lower transverse section 23 are located on the upper side of the top surface of the shell and the top of the shell cavity, respectively. During assembly, first, an outer insulating sheet 4 is fitted onto the outside of the grooved section 22 of the T-shaped component. The outer diameter of the outer insulating sheet 4 is larger than the outer diameter of the upper transverse section, and the inner diameter of the outer insulating sheet is equivalent to the outer diameter of the grooved section. Then, the T-shaped component with the outer insulating sheet 4 is inserted into the positive electrode through hole from the top side of the housing 1, so that the outer insulating sheet is located between the upper transverse section 21 and the top surface of the cylindrical battery housing.
[0013] After the T-shaped component is inserted into the positive electrode through hole, a rubber sealing ring 3, an inner insulating sheet 5, and a metal sheet 6 are sequentially fitted onto the grooved section 22 of the T-shaped component within the inner cavity of the housing. The rubber sealing ring 3 has an L-shaped vertical cross-section, with a horizontal portion 31 and a vertical portion 32. The vertical portion is located between the wall of the positive electrode through hole and the outer peripheral surface of the grooved section 22, and the outer diameter of the horizontal portion is larger than the inner diameter of the positive electrode through hole. The inner diameter of the inner insulating sheet 5 is larger than the inner diameter of the positive electrode through hole and is approximately equal to the outer diameter of the horizontal portion 31. The inner diameter of the metal sheet 6 is approximately equal to the outer diameter of the grooved section 22, and its outer diameter is larger than the inner diameter of the inner insulating sheet 5 but smaller than its outer diameter. The inner insulating sheet 5 is located between the metal sheet 6 and the top surface of the inner cavity of the housing 1, and the horizontal portion 31 is sandwiched between the metal sheet 6 and the top surface of the inner cavity of the housing 1.
[0014] After the metal sheet 6 is assembled, the T-shaped component is riveted to form the lower transverse section 23. The lower transverse section 23 presses against the metal sheet 6, axially limiting the metal sheet 6 and pressing it against the transverse part 31 and the inner insulating sheet 5. When the casing deforms due to excessive internal air pressure, the top of the casing bulges upward and outward. The internal air pressure squeezes the metal sheet, and the transverse part of the metal sheet presses the rubber sealing ring, keeping it tightly against the top surface of the inner cavity of the casing. Under compression, the vertical part of the rubber sealing ring can also deform and tightly adhere to the outer circumference of the groove section, forming a tight seal and improving the sealing effect.
Claims
1. A positive electrode sealing structure for a cylindrical battery, wherein the bottom of the cylindrical battery casing is closed and a positive electrode through-hole is provided at the top, and the positive electrode post of the cylindrical battery is disposed in the positive electrode through-hole, characterized in that: The positive electrode post has an annular groove on its outer circumferential surface. The vertical cross-section of the positive electrode post is "I"-shaped, forming an upper transverse section, a grooved section, and a lower transverse section from top to bottom. The grooved section of the positive electrode post is located in the positive electrode through hole. The upper and lower transverse sections are located on the upper side of the top surface of the housing and the top of the inner cavity of the housing, respectively. The grooved section is fitted with an outer insulating sheet, an inner insulating sheet, a metal sheet, and a rubber sealing ring. The outer insulating sheet is located between the upper transverse section and the top surface of the housing. The inner diameter of the metal sheet is smaller than the outer diameter of the lower transverse section, and the outer diameter is larger than the inner diameter of the lower transverse section. The inner insulating sheet has an inner hole diameter that is larger than the inner diameter of the positive electrode through hole. The inner insulating sheet is located between the metal sheet and the top surface of the inner cavity of the housing. The metal sheet is axially limited by the lower transverse section. The rubber sealing ring has an L-shaped vertical cross-section, with a transverse portion and a vertical portion. The outer diameter of the transverse portion is larger than the inner diameter of the positive electrode through hole but not larger than the inner hole diameter of the inner insulating sheet. The transverse portion has a part sandwiched between the metal sheet and the top surface of the inner cavity of the housing. The vertical portion has a part located between the wall of the positive electrode through hole and the outer peripheral surface of the groove section.
2. The cylindrical battery positive electrode sealing structure according to claim 1, characterized in that: The outer diameter of the outer insulating sheet is larger than the outer diameter of the upper transverse section, and the inner diameter of the outer insulating sheet is equivalent to the outer diameter of the groove section.
3. The cylindrical battery positive electrode sealing structure according to claim 1, characterized in that: The inner diameter of the metal sheet is equivalent to the outer diameter of the groove section, and the outer diameter is not greater than the outer diameter of the inner insulating sheet.